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Finding the Fourth Proportional to 78.30, 116.88 and 68.67

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Solution

The fourth proportional to 78.30, 116.88 and 68.67 is: 102.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.30 : 116.88 = 68.67 : x
  2. Step 2: Convert to fraction form
    78.30/116.88 = 68.67/x
  3. Step 3: Cross multiply
    78.30x = 116.88 × 68.67
  4. Step 4: Simplify right side
    78.30x = 8,026.15
  5. Step 5: Solve for x
    x = 8,026.15/78.30
  6. Step 6: Final answer
    x = 102.51

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.